V$CACHE_LOCK

This is a Real Application Clusters view. V$CACHE_LOCK is similar to V$CACHE, except for the platform specific lock manager identifiers. This information may be useful if the platform- specific lock manager provides tools for monitoring the PCM lock operations that are occurring. For example, first query to find the lock element address using INDX and CLASS, then query V$BH to find the buffers that are covered by the lock.

Column	Datatype	Description
`FILE#`	`NUMBER`	Datafile identifier number (to find filename, query `DBA_DATA_FILES` or `V$DBFILE`)
`BLOCK#`	`NUMBER`	Block number
`STATUS`	`VARCHAR2(6)`	Status of the block: `free` - Not currently in use `xcur` - Exclusive `scur` - Shared current `cr` - Consistent read `read` - Being read from disk `mrec` - In media recovery mode `irec` - In instance recovery mode
`XNC`	`NUMBER`	Number of parallel cache management (PCM) lock conversions due to contention with another instance
`NAME`	`VARCHAR2(30)`	Name of the database object containing the block
`KIND`	`VARCHAR2(12)`	Type of database object: `1` - Index `2` - Table `3` - Cluster `4` - View `5` - Synonym `6` - Sequence `7` - Procedure `8` - Function `9` - Package `10` - Nonexistent `11` - Package body `12` - Trigger `13` - Type `14` - Type body `19` - Table partition `20` - Index partition `21` - LOB `22` - Library `Null` - Unknown
`OWNER#`	`NUMBER`	Owner number
`LOCK_ELEMENT_ADDR`	`RAW(4 \| 8)`	Address of the lock element that contains the PCM lock that is covering the buffer. If more than one buffer has the same address, then these buffers are covered by the same PCM lock.
`LOCK_ELEMENT_NAME`	`NUMBER`	Address of the lock element that contains the PCM lock that is covering the buffer. If more than one buffer has the same address, then these buffers are covered by the same PCM lock.
`FORCED_READS`	`NUMBER`	Number of times the block had to be reread from the cache because another instance has forced it out of this instance's cache by requesting the lock on the block in exclusive mode
`FORCED_WRITES`	`NUMBER`	Number of times GCS had to write this block to cache because this instance had used the block and another instance had requested the lock on the block in a conflicting mode
`INDX`	`NUMBER`	Platform-specific lock manager identifier
`CLASS`	`NUMBER`	Platform-specific lock manager identifier

See Also: